1. Field of the Invention
The present disclosure relates to a thin-film transistor substrate and a display device comprising the same, and especially to a thin-film transistor substrate capable of reducing the series impedance between source/drain electrodes and the semiconductor layer and a display device comprising the same.
2. Description of Related Art
With the progressive development of display technology, all the devices are developed following the trend of minimization, thinness, light weight and so on, and the mainstream display devices have evolved from cathode ray tubes to the display devices (LCDs) or organic light emitting diode devices (OLEDs).
Typical thin film transistors (TFTs) are classified into the top gate structure and the bottom gate structure. Comparing the top gate oxide semiconductor TFT with the bottom gate oxide semiconductor TFT, the top gate structure has the advantages of: reducing the size of TFT for higher resolution; and reducing the parasitic capacitance between gate and source/drain electrodes to reduce signal distortion upon a display operation.
However, in the top gate structure, the series impedance between source/drain electrodes and the semiconductor layer is overly high, thus decreasing the on current of the thin film transistor, which in turn, results in problems such as insufficient charging of the storage capacitor and overly high power consumption.
In view of above, what is needed in the art is to develop a thin-film transistor substrate to solve the above problems to provide a display device with more stable quality and longer service lifetime.